Coils - Search Coil Shape - Rectangular

Rectangular Search Coils: Wide Sweep Coverage and Deep Seeking Performance

Rectangular search coils are a specialty shape built around a long, straight sweep path rather than the rounded footprint of standard coils. The elongated frame produces an even detection field across its full width, so each pass covers a consistent strip of ground with uniform depth from edge to edge. Most rectangular coils available today are large deep-seeking designs — including two-piece transmit and receive configurations — intended for hunters chasing big, deeply buried targets that standard coils cannot reach.

Two-Piece Transmit and Receive Coils – for Maximum Depth

The most common rectangular setups use separate transmitter and receiver frames mounted apart from one another, a layout closely related to classic two-box detecting. Separating the coils increases the depth of the detection field dramatically, at the cost of sensitivity to small surface targets. That trade-off is intentional: these coils are meant to ignore coins, pull tabs, and shallow trash while responding to large masses of metal well below the reach of a conventional search coil. The XP Xtrem Hunter XTR system is the best-known modern example, pairing with the Deus II to turn a standard detector into a deep-seeking machine.

Best Uses – Caches, Large Relics, and Buried Iron

Rectangular deep-seeking coils earn their place on sites where the target is big and the depth is beyond normal detecting range. Typical applications include cache hunting, large war relics and cannonballs, buried farm iron, foundation and structure location, and mapping out old wells, pipes, and tanks before digging. Because they cover a wide, consistent swath per pass, they also suit systematic gridding of large open sites where working the ground methodically matters more than pinpointing small finds.

What to Expect in the Field

These coils are larger and heavier than standard search coils, so a harness or support setup is common on longer hunts. Sweep speed is typically slower and more deliberate, and signals from deep targets tend to be broad and soft rather than sharp. Many detectorists use a rectangular deep-seeking coil as a second coil in the kit — covering a site first with a standard coil, then returning with the rectangular setup to check for anything larger sitting deeper.

Matching Coils to Your Detector

Rectangular coil compatibility is tied to specific detector models, connector types, and operating frequencies, so confirm fitment before ordering. Selection in this shape is limited compared to round and elliptical options, since deep-seeking systems are purpose-built by a small number of manufacturers. Use brand filters to find coils confirmed for your machine. See all search coils.

Related Guides: Metal Detector Coil Guide | Metal Detector Technologies